Valved piston compressor



y 6, 1952 s. F. WALKER 2,595,738

- VALVED PISTON COMPRESSOR Filed April 12, 1950 r -w IV IN VEN TOR.

BTTOKNEY Patented May 6, 1952 UNITED STATES Patent GFFICE VALVED PISTONCOMPRESSOR Stanley F. Walker, Montgomery, Ala. Application April 12,1950, Serial No. 155,380

1 Claim. 1

The present invention relates to improvements in compressors forrefrigerators and the like and, more specifically, to a new and improvedcompressor particularly well adapted for use in connection with midgetrefrigerators of the type described in my co-pending patent applicationSerial No. 722,317, filed January 16, 1947 now Patent No. 2,512,077dated June 20, 1950.

One object of the present invention is the provision of a device of thecharacter described which consists of fewer parts, and of parts whichare less expensive to manufacture and to assemble and which are lighterin weight, than has been the case with hitherto known compressors.

Another object of the present invention is the provision of a device ofthe character described which has movable parts and/or bearingsconsisting mainly of hard rubber or fibre so as to avoid to a largeextent the necessity of any lubrication, said movable parts being ofsuch a simple construction and being arranged in such a manner that theycan be exchanged quickly and at a very low cost when they are worn out.

A further object of the present invention is the provision of a deviceof the character described which is highly efficient and reliable inoperation, and which is simple and inexpensive to manufacture and tooperate, but which is also sturdy, durable and well adapted to Withstandthe rough usage to which devices of this type frequently are subjected.

With the foregoing and other objects in view which will appear as thedescription proceeds, the invention consists of certain novel details ofconstruction and combinations of parts hereinafter more fully describedand pointed out in the claim, it being understood that changes may bemade in the construction and arrangement of parts without departing fromthe spirit of the invention as claimed.

In the accompanying drawing a preferred form of the invention has beenshown.

In said drawing:

Figure 1 is a fractional sectional View on the line l-l of Fig. 2 of apreferred embodiment of my invention;

Fig. 2 is a fractional sectional view on the line 22 of Fig. 1;

Fig. 3 is a fractional sectional view on the line 3-3 of Fig. 2;

Fig. 4 is a fractional sectional view on the line 4-4 of Fig. 2;

Fig. 5 is a reduced fractional vertical sectional view showing themovable parts in a certain position different from the position shown inFigs. 1 and 2;

Fig. 6 is a reduced fractional vertical sectional view as Fig. 5 showingthe movable parts in another position; and

, Fig. '7 is a reduced sectional view as Figs. 5 and 6 showing themovable parts in still another position.

Similar reference numerals refer to similar parts throughout the severalviews.

In the drawing the numeral 2 denotes a housing which has a cylindricalportion 4, that is open at its top, and a lower portion 6 of acrank-caselike shape whose interior preferably is substantiallyrectangular in cross-section. A piston 8, which preferably is made ofhard rubber, plastic material, or the like, is adapted to bereciprocated in the cylindrical portion 4. A substantially rectangularportion Ill extends downwardly from the piston 8 into the lower portion6 of the housing 2 and is so dimensioned that there is always some freespace between it and the inner sides of the portion 6. The piston 8 isprovided with a vertical bore l2, which extends preferably through theaxial section of the piston 8 and whose lower end portion is bifurcatedat M, or diverging, and terminates at the lateral ,lower extremity ofthe piston 8, as may be seen in Fig. 1. A horizontal bore [6 extendsthrough a lateral section of the piston 3 from its periphery andterminates into the bore [2. The top of the piston 8 preferably isprovided with an excavation l8 into which is placed a non-return-checkvalve 2!] of the flapper valve type having a flapper 22, or the like,adapted for closing the bore l2 whenever there is pressure above thepiston 8, and to open the same whenever there is a vacuum above thepiston 8. Any suitable cover is secured to the top of the cylinder 8,for instance a disk 24 having a perforation 26 is secured thereto bymeans of screws 28 or the like. A spring so preferably is interposedbetween the parts 25) and 24 and tends to force the piston 8 away fromthe cover 24. A dome-shaped member 32, to which is connected an outletpipe 34, is fastened upon the disk 24 by the screws 28 or the like, andpacking or gasket means 36 preferably are interposed between the disk 24and the member 34 as well as the cylinder 3. The parts 24 and 32preferably are provided with opposite excavations in which rests anon-return-check valve 38 of the flapper valve type or of any othersuitable type.

An inlet pipe 40 is connected to a bore 42 (Figs. 1 and 6) in a sectionof the wall of the cylinder portion 4. The bore 42 registers with thebore [6 in the piston 8 when the latter is in its lowermost position(Figs. 1 and 2). The pipe 40 preferably is provided with a shut-offvalve 42 and is connected to a liquid receptacle 44 or the like.

The portion [0 is provided with an oblong perforation 46 which isengaged by a cam 48, that is provided on a shaft 50. A bearing bracket52 is secured to one side of the lower portion of the housing 2, and abearing bushing 54 is provided in a horizontal bore 56 in the housing 2opposite the bracket 52. The shaft 50 rotates in the parts 52 and 54,and can be driven by a pulley 58 or the like. Any suitable packing means60 (Fig. 1) are provided in the bracket 52 and are spaced from eachother by means of a coiled spring 62 or the like. If the housing 2 andthe bracket 52 are made of the same or a similar material as the piston8, no bearing bushings are necessary.

If the parts 48, 50 and 58 revolve in a clockwise direction, thefollowing mode of operation is apparent: While moving from the positionshown in Figs. 1 and 2 to that shown in Fig. 6, the piston 8 movesupwardly, the valve 38 is open, and the valve 20 is closed (Fig. 5), sothat fluid above the piston 8 will be forced out of the cylindricalportion 4 through the parts 24, 3B, 32 and 34. Simultaneously there willbe created a suction force and a vacuum in the portion 6, and as long asthe bore I6 is adjacent the bore 42 or any part of it, fluid will bedrawn into the portion 6 through the pipe 40 as well as through l6, l2and I4. While the movement continues from the position shown in Fig. 6to that shown in Fig. 7, the piston 8 moves downwardly, the valve 38 isclosed, and the valve 29 is open, so that the fluid in the portion 6will be compressed and will be forced into the cylindrical portion 4through [4, l2, and 20, the bores i5 and 42 being no longer adjacenteach other or in registering alignment so that no fluid can move backinto the pipe 49. Upon continuation of the rotation of the shaft, themoving parts reach again the position shown in Figs. 1 and 2.

Thus my new and improved compressor works substantially on a two-cycleprinciple. The cam 43 preferably has four raised circumferentialsections 84, 9B, 68 and 10 (Figs. 1 and 2), whose arrangement exactlycontrols the movement of the piston 8 during each part of eachrevolution of the cam 48.

Since certain changes may be made in the above article and differentembodiments of the invention could be made without departing from thescope thereof, it is intended that all matter contained in the abovedescription or shown in the accompanying drawing shall be interpreted asillustrative and not in a limiting sense.

It is also to be understood that the following claim is intended tocover all of the generic I and specific features of the invention hereindescribed, and all statements of the scope of the invention which as amatter of language might be said to fall therebetween.

Having thus fully described my said invention, what I claim as new anddesire to secure by Letters Patent is:

A device of the character described comprising a housing whose upperportion is cylindrical and has an opening in its lower wall sectionwhile the lower portion of the housing is shaped as a crankcase portion,a disk having an aperture in its center portion being secured to theupper end of the cylindrical portion of said housing, a piston ofplastic material adapted to be reciprocated in said cylindrical portionhaving a perforation axially extended therethrough as Well as a lateralbore extending from its periphery into said perforation, a firstnon-return-check valve at the top of said piston adapted for opening andclosing said perforation, a second non-return-check valve provided atsaid perforated disk being adapted for closing the aperture in said diskwhenever there is a vacuum within said cylindrical portion, a springinterposed between said disk and said piston adapted for forcing thelatter away from the former and resting with its lower end upon saidfirst nonreturn-check valve, a flattened portion secured to said pistonand extending into said crankcase portion and having an oblong openingwhose longitudinal axis is right angularly disposed to the axis of saidpiston, a shaft being rotatable in said crankcase portion, and a camprovided on said shaft adapted for engaging the side of said oblongopening in said flattened portion and being adapted to cause areciprocating movement of said piston when the shaft revolves, saidlateral bore in said piston being so located as to register with theopening in the lower section of the cylindrical portion of said housingwhen said piston is in its lowermost position, and that portion of saidperforation which is adjacent said flattened portion being V-shaped andterminating at the lateral extremities of said piston adjacent saidflattened portion.

STANLEY F. WALKER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 279,699 Bowman June 19, 18831,917,690 Beeh July 11, 1933 2,040,667 Moulet May 12, 1936 2,344,565Scott et al Mar. 21, 1944 2,512,077 Walker June 20, 1950 FOREIGN PATENTSNumber Country Date 427,910 Great Britain May 2, 1935

